Cost effective energy storages, feasible for storing energy from new and traditional sources and delivering the energy when needed, is a “missing link” for improved exploitation of new and existing energy sources.
Storage of energy allows delivery at times when variable sources cannot deliver, providing stability and allowing a larger proportional part of the energy sources to be renewable and friendly to the environment. In addition, the maximum delivery can be increased, since both the sources and the storages can deliver energy at the same time, and the networks for transfer of electrical energy or thermal energy can be smaller since storages can be located where the demand is found.
In patent publication WO 20121169900 A1, a Thermal Energy Storage (TES) is described, having beneficial properties over prior art storages. More specifically, a practical and cost effective solution is provided for a thermal storage using solid-state material as the main storage medium, allowing storage of energy as high temperature heat, which means heat energy at temperature sufficiently high to convert the heat effectively into electric power in a turbine-generator set or equivalent means.
In international patent application PCT/NO2013/050120, it is described how thermal energy storages like those according to the teaching of WO 2012/169900 A1 are beneficial in order to simplify and increase efficiency of energy plants of various types, such as concentrated solar power plants and nuclear power plants.
Some relevant art has been developed by Deutches Zentrum für Luft- and Ramfarth e.V. (DLR), such as described in patent publication DE 10 2009 036 550 A1. However, the thermal energy storages of DLR are rather difficult and expensive to build for a large-scale storage. Furthermore, said storages are not easy to handle and transport, are not particularly feasible for modular stacking and modular thermal storage scale-up or scale-down, have large footprints with respect to storage capacity provided, have large heat loss due to high surface to volume ratio, are not feasible for containing or identifying the exact position of possible leakage of heat transfer fluid, and are not feasible for easy repair or replacement or bypass/isolation of modular or smaller parts of the storage.
Despite recent significant steps forward, provided by the technology described above, it is still a demand for improvements. The effect/cost ratio is always in demand for improvement, as well as the versatility and flexibility of the thermal energy storage with respect to sources of energy. The objective of the present invention is to meet growing needs and demands with new technology, providing improvement with respect to one or several of the issues mentioned above.